Portion of a motor grader



FIG. 1 is a top left rear perspective view of a portion of a motor grader showing our new design;

FIG. 2 is a top view thereof;

FIG. 3 is a right side view thereof;

FIG. 4 is a left side view thereof;

FIG. 5 is a front view thereof; and,

FIG. 6 is a rear view thereof.

The elements depicted in broken lines form no part of the claimed design. 

The ornamental design for a portion of a motor grader, as shown and described. 